Since the advent of computer technology first made them possible, vehicle simulators have been used for a number of purposes, including research, training, and vehicle engineering. Simulators have become increasingly prevalent and useful for reproducing the experience of operating aircraft, motor vehicles, trains, spacecraft, and other vehicles. Aviation simulators have become particularly prevalent, with nearly every airline now using simulators for training and research—the first time a commercial pilot flies a new aircraft, it is often filled with passengers. The military services use simulators extensively for training personnel in the operation of ships, tanks, aircraft, and other vehicles.
Despite their varied usage, simulators, especially those providing the operator(s) with motion cues, have primarily remained the tools of large organizations with significant financial resources. The use of motor vehicle (i.e., driving) simulators has not yet progressed beyond manufacturers, suppliers, government agencies (including the military), and academic institutions, largely because of their cost. However, driving simulators have a number of valuable safety applications. First, they offer research into driver response behavior. Highways are becoming populated by more vehicles, moving at greater speeds, with a greater portion of drivers comprised of older adults with reduced sensory and response capabilities. Cellular telephones, navigation systems, and other devices (often developed by third parties and added to vehicles without suitable integration with manufacturer-supplied devices) place increased demands on the driver's attention, and drugs continually arrive on the market that affect driver alertness. These factors mandate a better understanding of driver limitations, particularly those of older drivers. Researching driver behavior in emergencies by examination of real accidents has limited yield, because every accident is unique to some extent, determining causation is difficult, and controlled experimental research is inherently not possible for real accidents. Driving simulators could provide data on the driver's response to emergency situations without exposure to actual risk.
Second, simulators can provide an improved means for training and evaluating drivers. Most driver training is conducted either in classrooms or in automobiles in normal traffic, which rarely exposes trainees to unexpected hazards. Devices that would allow trainees to experience potential collision situations, visibility hazards, or other unusual driving situations, without actual exposure to risk would provide useful training.
Third, simulators provide manufacturers and suppliers useful data from which to further develop their products. Vehicle manufacturers, suppliers and car/truck fleet owners usually perform developmental tests in actual vehicles, but this is limited to experiences not involving collision or other hazards. The use of simulators to perform these functions is costly, particularly for programming and measuring motion and configuring the simulator to represent the appropriate vehicle, limiting the usefulness of these simulators for most research applications.
Simulators are primarily tasked with recreating the sensory cues their “real-world experience” counterparts offer. Most state of the art simulators do a credible job recreating visual and audible stimuli, but only the most expensive provide credible cues for the vestibular senses (controlled by semicircular canals in the inner ear, which sense rotary acceleration, and otolith organs, which sense translational acceleration) and the muscle and joint sensors of motion. Motor vehicle simulators, in particular, struggle to provide a faithful motion representation without exorbitant cost. Because of the cost of providing such functionality, relatively few driving simulators even attempt to provide motion cues, despite the fact that tests reveal subjects tend to over-steer or experience vertigo because of a mismatch between visual and motion cues. Those that provide motion cues usually do so with an expensive hydraulic simulator base, but very few motion-base driving simulators are in use, and even these lack the ability to accurately convey translational acceleration. Some state of the art simulators promise to rectify this problem, but this capability typically entails a significant cost. Clearly, simulators that represent motion cues faithfully are not cost-effective research or training tools for most applications. FIG. 1 shows the state-of-the-art National Advanced Driving Simulator operated by University of Iowa for the Department of Transportation. Motion fidelity requires the test driver to ride inside a cab moving on a 20×20 meter X-Y hydraulic motion platform while viewing a computer-generated 360 degree screen.
The same financial barriers that prevent more widespread use of driving simulators have also prevented the development of simulators for the operation of wheelchairs, skis, snowboards, and many other vehicles which move, sometimes at high speeds, when in actual operation. Clearly the availability of more cost-effective simulators could enable better research, training, and engineering, resulting in safer and more user-friendly vehicles, both those indicated above and others, and in better, safer operation thereof.